Portal:Energy

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Introduction

A plasma globe, using electrical energy to create plasma, light, heat, movement and a faint sound

In physics, energy (from Ancient Greek ἐνέργεια (enérgeia) 'activity') is the quantitative property that is transferred to a body or to a physical system, recognizable in the performance of work and in the form of heat and light. Energy is a conserved quantity—the law of conservation of energy states that energy can be converted in form, but not created or destroyed; matter and energy may also be converted to one another. The unit of measurement for energy in the International System of Units (SI) is the joule (J).

Common forms of energy include the kinetic energy of a moving object, the potential energy stored by an object (for instance due to its position in a field), the elastic energy stored in a solid object, chemical energy associated with chemical reactions, the radiant energy carried by electromagnetic radiation, and the internal energy contained within a thermodynamic system. All living organisms constantly take in and release energy.

Due to mass–energy equivalence, any object that has mass when stationary (called rest mass) also has an equivalent amount of energy whose form is called rest energy, and any additional energy (of any form) acquired by the object above that rest energy will increase the object's total mass just as it increases its total energy.

Human civilization requires energy to function, which it gets from energy resources such as fossil fuels, nuclear fuel, or renewable energy. The Earth's climate and ecosystems processes are driven by the energy the planet receives from the Sun (although a small amount is also contributed by geothermal energy). (Full article...)

Selected article

Renewable energy in Iceland has supplied over 70% of Iceland's primary energy needs since 1999 - proportionally more than any other country - and 99.9% of Iceland's electricity is generated from hydroelectricity and geothermal power. In 1998 the Icelandic Parliament committed to convert the national vehicle and fishing fleets to hydrogen fuel produced from renewable energy by 2050. This would make Iceland the first completely energy-independent country in the world to use 100% renewable energy sources.

Iceland's location on the Mid-Atlantic Ridge makes it one of the most tectonically active places in the world, with over 200 volcanoes and over 20 high-temperature steam fields. Geothermal energy for heating was first used in 1907 when a farmer piped steam from a hot spring into his house. In 1930, the first pipeline was constructed in Reykjavík, heating two schools, 60 homes, and the main hospital. In 1943, the first geothermal district heating company started. Geothermal power now heats 89% of the nation's houses, provides around 19% of electricity generation and over 54% of primary energy. The first hydroelectric plant was built in 1904 and produced 9 kW of power. Hydropower now provides 81% of Iceland's electricity supply.

Imported oil provides most of Iceland's remaining energy. Replacing this with hydrogen was first suggested after the 1970s energy crisis, but the idea was not adopted until 1998. Iceland's small size makes it ideal for testing the viability of hydrogen as a fuel source for the future, while the plentiful renewable energy sources can be harnessed for its production. Iceland participates in international hydrogen fuel research and development programs, and many countries are following the nation's progress.

As a result of its transition to renewable energy, Iceland is ranked 53rd in the list of countries by carbon dioxide emissions per capita in 2003, emitting 62% less than the United States despite using more primary energy per capita.

Selected image

Photo credit: From an image by Arnold Paul
Coal-fired power stations transform chemical energy into 36%-48% electricity and 52%-64% waste heat.

Did you know?

Cyclone Catarina from the ISS on March 26 2004

• According to research by the IPCC, government funding for most energy research programmes has been flat or declining for nearly 20 years, and is now about half the 1980 level?

• Renewable energy in Iceland provides over 70% of the country's primary energy needs, and 99.9% of Iceland's electricity?

• The Rance tidal power plant in France was the world's 1st electrical generating station powered by tidal energy?

• A tropical cyclone (example pictured) can release heat energy at the rate of 50 to 200 trillion joules per day, roughly 200 times the world-wide electrical generating capacity?

• Ordinary fossil fuel power plants convert between 36% and 48% of the fuel's energy into electricity, with the remainder being lost as waste heat, about half of which is unavoidable due to the second law of thermodynamics?

• Burning biomass indoors leads to between 1.5 and 2 million deaths each year from indoor air pollution in developing nations?

• Over 50% of world small hydroelectricity generating capacity is in China?

• Charles Fritts developed the first solar cell in 1884, although its efficiency was less than 1%?

Selected biography

Marion King Hubbert (1903–1989) was a geophysicist who made several important contributions to geology and geophysics, most notably the Hubbert curve and Hubbert peak theory (or peak oil), with important political ramifications.

Born in Texas, Hubbert studied geology, mathematics, and physics at the University of Chicago. He pursued his Ph.D. while working for the Amerada Petroleum Company, then worked for the Shell Oil Company from 1943 until 1964. On leaving Shell he became a senior research geophysicist for the United States Geological Survey until retiring in 1976. Hubbert was also a professor at Stanford University and at UC Berkeley.

Hubbert is most well-known for his studies on the capacities of oil fields and natural gas reserves. He predicted that, for any given geographical area, the rate of petroleum production over time would resemble a bell curve. At the 1956 meeting of the American Petroleum Institute, Hubbert predicted that United States petroleum production would peak in the late 1960s or early 1970s. He became famous when his prediction came true in 1970.

In 1974, Hubbert projected that global oil production would peak in 1995 "if current trends continue". Various subsequent predictions have been made by others as trends have fluctuated in the intervening years. Hubbert's theory, and its implications for the world economy, remain controversial.

In the news

15 June 2024 – Russian invasion of Ukraine

The United States announces a $1.5 billion aid package to Ukraine, focused primarily on the country's energy industry and humanitarian assistance. (Politico)

1 June 2024 – Russian invasion of Ukraine

Russia launches missile and drone strikes across Ukraine, injuring at least four people and damaging critical infrastructure, including energy facilities. Ukraine says that it shot down 35 of 53 missiles and 46 of 47 drones. (Reuters)

General images

The following are images from various energy-related articles on Wikipedia.

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  The oil refinery in Haifa, Israel, is capable of processing about 9 million tons (66 million barrels) of crude oil a year. Its two cooling towers are landmarks of the city's skyline. (from Oil refinery)
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  Pile of asphalt-covered aggregate for formation into asphalt concrete (from Oil refinery)
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  Sulphur (from Oil refinery)
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  Since 1985, the proportion of electricity generated from low-carbon sources has increased only slightly. Advances in deploying renewables have been mostly offset by declining shares of nuclear power. (from Sustainable energy)
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  Greenhouse gas emissions per energy source. Solar power is one of the sources with the least greenhouse gas emissions. (from Solar power)
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  Construction close to high pressure gas transmission pipelines is discouraged, often with standing warning signs. (from Natural gas)
• 
  Nuclear fuel assemblies being inspected before entering a pressurized water reactor in the United States (from Nuclear power)
• 
  Australia (from Solar power)
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  A parabolic collector concentrates sunlight onto a tube in its focal point. (from Solar power)
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  United States and USSR/Russian nuclear weapons stockpiles, 1945–2006. The Megatons to Megawatts Program was the main driving force behind the sharp reduction in the quantity of nuclear weapons worldwide since the cold war ended. (from Nuclear power)
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  The location of shale gas compared to other types of gas deposits (from Natural gas)
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  A breakdown of the products made from a typical barrel of US oil (from Oil refinery)
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  Natural gas processing plant in Aderklaa, Lower Austria (from Natural gas)
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  Wind turbines in Xinjiang, China
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  Global geothermal electric capacity. Upper red line is installed capacity; lower green line is realized production. (from Geothermal power)
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  Fire-extinguishing operations after the Texas City refinery explosion (from Oil refinery)
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  Measurement of the tailrace and forebay rates at the Limestone Generating Station in Manitoba, Canada. (from Hydroelectricity)
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  Sample of gasoline (from Oil refinery)
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  World map showing where people without access to electricity lived in 2016⁠—mainly in sub-Saharan Africa and the Indian subcontinent (from Sustainable energy)
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  The outdoor section of a heat pump. In contrast to oil and gas boilers, they use electricity and are highly efficient. As such, electrification of heating can significantly reduce emissions. (from Sustainable energy)
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  Several countries and the European Union have committed to dates for all new cars to be zero-emissions vehicles. (from Sustainable energy)
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  Sample of kerosene (from Oil refinery)
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  Map of solar resources from World bank (from Solar power)
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  Cracks at the historic Town Hall of Staufen im Breisgau presumed due to damage from geothermal drilling (from Geothermal power)
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  Schematics of a grid-connected residential PV power system (from Solar power)
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  Countries by natural gas proven reserves (2014), based on data from The World Factbook (from Natural gas)
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  Part of the Senftenberg Solarpark, a solar photovoltaic power plant located on former open-pit mining areas close to the city of Senftenberg, in Eastern Germany. The 78 MW Phase 1 of the plant was completed within three months. (from Solar power)
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  Activity of spent UOx fuel in comparison to the activity of natural uranium ore over time (from Nuclear power)
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  The first light bulbs ever lit by electricity generated by nuclear power at EBR-1 at Argonne National Laboratory-West, December 20, 1951. (from Nuclear power)
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  The Warwick Castle water-powered generator house, used for the generation of electricity for the castle from 1894 until 1940 (from Hydroelectricity)
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  The 120-MW_e Nesjavellir power station in southwest Iceland (from Geothermal power)
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  Passive cooling features, such as these windcatcher towers in Iran, bring cool air into buildings without any use of energy. (from Sustainable energy)
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  A sugarcane plantation to produce ethanol in Brazil (from Sustainable energy)
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  Natural gas drilling rig in Texas, US (from Natural gas)
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  Anti-nuclear protest near nuclear waste disposal centre at Gorleben in northern Germany (from Nuclear power)
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  Olkiluoto 3 under construction in 2009. It was the first EPR, a modernized PWR design, to start construction. (from Nuclear power)
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  Grangemouth Refinery, in Scotland (from Oil refinery)
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  Anacortes Refinery, on the north end of March Point southeast of Anacortes, Washington, United States (from Oil refinery)
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  Battery storage facility
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  A micro-hydro facility in Vietnam (from Hydroelectricity)
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  Polyethylene plastic main being placed in a trench (from Natural gas)
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  Electrified transport and renewable energy are key areas of investment for the renewable energy transition. (from Sustainable energy)
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  Europe (from Solar power)
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  Gas network emergency vehicle responding to a major fire in Kyiv, Ukraine (from Natural gas)
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  Growth of worldwide nuclear power generation (from Nuclear power)
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  Acceptance of wind and solar facilities in one's community is stronger among U.S. Democrats (blue), while acceptance of nuclear power plants is stronger among U.S. Republicans (red). (from Solar power)
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  Life-cycle greenhouse gas emissions of electricity supply technologies, median values calculated by IPCC (from Nuclear power)
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  Deaths caused by use of fossil fuels such as natural gas (areas of rectangles in chart) greatly exceed those resulting from production of renewable energy (rectangles barely visible in chart). (from Natural gas)
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  A pipeline odorant injection station (from Natural gas)
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  The guided-missile cruiser USS Monterey (CG 61) receives fuel at sea (FAS) from the Nimitz-class aircraft carrier USS George Washington (CVN 73). (from Nuclear power)
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  US Natural Gas Marketed Production 1900 to 2012 (US EIA data) (from Natural gas)
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  The Ikata Nuclear Power Plant, a pressurized water reactor that cools by using a secondary coolant heat exchanger with a large body of water, an alternative cooling approach to large cooling towers (from Nuclear power)
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  Guri Dam, a hydroelectric dam in Venezuela (from Sustainable energy)
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  Clean energy investment has benefited from post-pandemic economic recovery, a global energy crisis involving high fossil fuel prices, and growing policy support across various nations. (from Sustainable energy)
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  Proportions of the isotopes uranium-238 (blue) and uranium-235 (red) found in natural uranium and in enriched uranium for different applications. Light water reactors use 3–5% enriched uranium, while CANDU reactors work with natural uranium. (from Nuclear power)
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  The launching ceremony of the USS Nautilus January 1954. In 1958 it would become the first vessel to reach the North Pole. (from Nuclear power)
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  Manhole for domestic gas supply, London, UK (from Natural gas)
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  A geothermal power station in Negros Oriental, Philippines (from Geothermal power)
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  Yearly hydro generation by continent (from Hydroelectricity)
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  The warming influence (called radiative forcing) of long-lived greenhouse gases has increased substantially in the last 40 years, with carbon dioxide and methane being the dominant drivers of global warming. (from Natural gas)
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  A Washington, D.C. Metrobus, which runs on natural gas (from Natural gas)
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  A photovoltaic power station in California, United States
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  motor oil (from Oil refinery)
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  Crude oil is separated into fractions by fractional distillation. The fractions at the top of the fractionating column have lower boiling points than the fractions at the bottom. The heavy bottom fractions are often cracked into lighter, more useful products. All of the fractions are processed further in other refining units. (from Oil refinery)
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  The multi-mission radioisotope thermoelectric generator (MMRTG), used in several space missions such as the Curiosity Mars rover (from Nuclear power)
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  Natural gas burning on a gas stove (from Natural gas)
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  South and South-East Asia (from Solar power)
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  The Ffestiniog Power Station can generate 360 MW of electricity within 60 seconds of the demand arising. (from Hydroelectricity)
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  Benefitting from favorable policies and declining costs of modules, photovoltaic solar installation has grown consistently, with China expected to account for 50% of new global solar photovoltaic projects by 2024. (from Solar power)
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  The Three Gorges Dam in Central China is the world's largest power-producing facility of any kind. (from Hydroelectricity)
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  Actual annual deployments of solar PV vs predictions by the IEA for the period 2002–2016. Predictions have largely and consistently underestimated actual growth. (from Solar power)
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  Comparison of natural gas prices in Japan, United Kingdom, and United States, 2007–2011 (from Natural gas)
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  Cooling towers at a geothermal power plant in Larderello, Italy
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  The Leibstadt Nuclear Power Plant in Switzerland (from Nuclear power)
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  Bloomberg NEF reported that in 2022, global energy transition investment equaled fossil fuels investment for the first time. (from Sustainable energy)
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  Jamnagar Refinery, the world's largest oil refinery, in Gujarat, India (from Oil refinery)
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  Sample of diesel fuel (from Oil refinery)
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  Typical composition of uranium dioxide fuel before and after approximately three years in the once-through nuclear fuel cycle of a LWR (from Nuclear power)
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  Seasonal cycle of capacity factors for wind and photovoltaics in Europe shown under idealized assumptions. The figure illustrates the balancing effects of wind and solar energy at the seasonal scale (Kaspar et al., 2019). (from Solar power)
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  Deaths caused as a result of fossil fuel use (areas of rectangles in chart) greatly exceed those resulting from production of sustainable energy (rectangles barely visible in chart). (from Sustainable energy)
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  A comparison of prices over time for energy from nuclear fission and from other sources. Over the presented time, thousands of wind turbines and similar were built on assembly lines in mass production resulting in an economy of scale. While nuclear remains bespoke, many first of their kind facilities added in the timeframe indicated and none are in serial production. Our World in Data notes that this cost is the global average, while the 2 projects that drove nuclear pricing upwards were in the US. The organization recognises that the median cost of the most exported and produced nuclear energy facility in the 2010s the South Korean APR1400, remained "constant", including in export.
  LCOE is a measure of the average net present cost of electricity generation for a generating plant over its lifetime. As a metric, it remains controversial as the lifespan of units are not independent but manufacturer projections, not a demonstrated longevity. (from Nuclear power)
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  Storage tanks and towers at Shell Puget Sound Refinery (Shell Oil Company), Anacortes, Washington (from Oil refinery)
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  Oil refinery in Iran (from Oil refinery)
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  Kenyan dairy farmer lighting a biogas lamp. Biogas produced from biomass is a renewable energy source that can be burned for cooking or light. (from Sustainable energy)
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  Following the 2011 Fukushima Daiichi nuclear disaster, the world's worst nuclear accident since 1986, 50,000 households were displaced after radiation leaked into the air, soil and sea. Radiation checks led to bans of some shipments of vegetables and fish. (from Nuclear power)
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  Reactor decay heat as a fraction of full power after the reactor shutdown, using two different correlations. To remove the decay heat, reactors need cooling after the shutdown of the fission reactions. A loss of the ability to remove decay heat caused the Fukushima accident. (from Nuclear power)
• 
  Refinery of Slovnaft in Bratislava (from Oil refinery)
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  Geothermal generation by country, 2021 (from Geothermal power)
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  Russia was a key oil and gas supplier to Europe (map from 2013). This changed with the Russian invasion of Ukraine in 2022. (from Energy policy)
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  The share of electricity production from solar, 2022 (from Solar power)
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  The nuclear fuel cycle begins when uranium is mined, enriched, and manufactured into nuclear fuel (1), which is delivered to a nuclear power plant. After use, the spent fuel is delivered to a reprocessing plant (2) or to a final repository (3). In nuclear reprocessing, 95% of spent fuel can potentially be recycled to be returned to use in a power plant (4). (from Nuclear power)
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  Installed geothermal energy capacity, 2022 (from Geothermal power)
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  Yearly solar generation by continent (from Solar power)
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  Thomas Young - the first to use the term "energy" in the modern sense, in 1802. (from History of energy)
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  Pico hydroelectricity in Mondulkiri, Cambodia (from Hydroelectricity)
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  The town of Pripyat abandoned since 1986, with the Chernobyl plant and the Chernobyl New Safe Confinement arch in the distance (from Nuclear power)
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  Ivanpah Solar Electric Generating System with all three towers under load (from Solar power)
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  Share of electricity production from nuclear, 2022 (from Nuclear power)
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  Schematic flow diagram of a typical natural gas processing plant (from Natural gas)
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  Utility cycling infrastructure, such as this bike lane in Vancouver, encourages sustainable transport. (from Sustainable energy)
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  Construction of the Salt Tanks which provide efficient thermal energy storage so that output can be provided after sunset, and output can be scheduled to meet demand requirements. The 280 MW Solana Generating Station is designed to provide six hours of energy storage. This allows the plant to generate about 38% of its rated capacity over the course of a year. (from Solar power)
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  Part of the 354 MW Solar Energy Generating Systems (SEGS) parabolic trough solar complex in northern San Bernardino County, California (from Solar power)
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  Sample of crude oil (petroleum) (from Oil refinery)
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  The growth of solar PV on a semi-log scale since 1996 (from Solar power)
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  Refinery, Bayport Industrial Complex, Harris County, Texas (from Oil refinery)
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  Share of electricity production from hydropower, 2022 (from Hydroelectricity)
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  Schematic flow diagram of a typical crude oil distillation unit as used in petroleum crude oil refineries (from Oil refinery)
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  Electricity production by source (from Solar power)
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  Yearly geothermal generation by continent (from Geothermal power)
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  Example of energy policy decisions: The goal of the Southern Gas Corridor, which connects the giant Shah Deniz gas field in Azerbaijan to Europe, is to reduce Europe's dependency on Russian gas. (from Energy policy)
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  Global energy usage is highly unequal. High income countries such as the United States and Canada use 100 times as much energy per capita as some of the least developed countries in Africa. (from Sustainable energy)
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  Most waste packaging, small-scale experimental fuel recycling chemistry and radiopharmaceutical refinement is conducted within remote-handled hot cells. (from Nuclear power)
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  Baton Rouge Refinery (the fifth-largest in the United States) (from Oil refinery)
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  Buildings in the Solar Settlement at Schlierberg, Germany, produce more energy than they consume. They incorporate rooftop solar panels and are built for maximum energy efficiency. (from Sustainable energy)
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  Peoples Gas Manlove Field natural gas storage area in Newcomb Township, Champaign County, Illinois. In the foreground (left) is one of the numerous wells for the underground storage area, with an LNG plant, and above-ground storage tanks are in the background (right). (from Natural gas)
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  Geothermal power center in the Usulután Department, El Salvador (from Geothermal power)
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  Museum Hydroelectric power plant "Under the Town" in Užice, Serbia, built in 1900. (from Hydroelectricity)
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  Nuclear waste flasks generated by the United States during the Cold War are stored underground at the Waste Isolation Pilot Plant (WIPP) in New Mexico. The facility is seen as a potential demonstration for storing spent fuel from civilian reactors. (from Nuclear power)
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  Dry cask storage vessels storing spent nuclear fuel assemblies (from Nuclear power)
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  Enhanced geothermal system 1:Reservoir 2:Pump house 3:Heat exchanger 4:Turbine hall 5:Production well 6:Injection well 7:Hot water to district heating 8:Porous sediments 9:Observation well 10:Crystalline bedrock (from Geothermal power)
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  Schematic of the ITER tokamak under construction in France (from Nuclear power)
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  The Calder Hall nuclear power station in the United Kingdom, the world's first commercial nuclear power station. (from Nuclear power)
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  The status of nuclear power globally (click for legend) (from Nuclear power)
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  Net metering, unlike a feed-in tariff, requires only one meter, but it must be bi-directional. (from Solar power)
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  The Hoover Dam in the United States is a large conventional dammed-hydro facility, with an installed capacity of 2,080 MW. (from Hydroelectricity)
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  Trends in the top five natural gas-producing countries (US EIA data) (from Natural gas)
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  Neste Oil refinery in Porvoo, Finland (from Oil refinery)
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  Burning of natural gas coming out of the ground (from Natural gas)
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  Hydro generation by country, 2021 (from Hydroelectricity)
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  A gas bill from Baltimore, Maryland, 1834, for manufactured coal gas, before the introduction of ground-extracted methane gas. (from Natural gas)
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  North America (from Solar power)
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  Community solar farm in the town of Wheatland, Wisconsin (from Solar power)
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  A woman in rural Rajasthan, India, collects firewood. The use of wood and other polluting fuels for cooking causes millions of deaths each year from indoor and outdoor air pollution. (from Sustainable energy)
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  Africa and Middle East (from Solar power)
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  Merowe Dam in Sudan. Hydroelectric power stations that use dams submerge large areas of land due to the requirement of a reservoir. These changes to land color or albedo, alongside certain projects that concurrently submerge rainforests, can in these specific cases result in the global warming impact, or equivalent life-cycle greenhouse gases of hydroelectricity projects, to potentially exceed that of coal power stations. (from Hydroelectricity)
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  Cylinders of liquified petroleum gas (from Oil refinery)
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  Death rates from air pollution and accidents related to energy production, measured in deaths in the past per terawatt hours (TWh) (from Nuclear power)
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  South America (from Solar power)
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  For cooking, electric induction stoves are one of the most energy-efficient and safest options. (from Sustainable energy)
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  Trends in the top five geothermal electricity-generating countries, 1980–2012 (US EIA) (from Geothermal power)
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  Natural gas extraction by countries in cubic meters per year around 2013 (from Natural gas)

Quotations

• "My administration is committed to a leadership role on the issue of climate change. We recognize our responsibility and will meet it - at home, in our hemisphere, and in the world." – George W. Bush, 2001
• "While the Kyoto Protocol is a crucial step forward, that step is far too small. And as we consider how to go further still, there remains a frightening lack of leadership." – Kofi Annan, 2006
• "It is going to be very difficult to keep temperature increases down to between 2 and 3 degrees centigrade [3.6 - 5.4°F]. We should work very hard to do that." – Nicholas Stern, 2006
• "Halting global warming requires urgent, unprecedented international cooperation, but the needed actions are feasible and have additional benefits for human health, agriculture and the environment." – James E. Hansen, 2004

Related portals

WikiProjects

WikiProjects connected with energy:

• WikiProject Energy
• Oil megaprojects task force

Other WikiProjects that may be of interest:

• WikiProject Environment
• WikiProject Technology
• WikiProject Biography

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